function array_diff_key (arr1) {
  // http://kevin.vanzonneveld.net
  // +   original by: Ates Goral (http://magnetiq.com)
  // +    revised by: Brett Zamir (http://brett-zamir.me)
  // +    input by: Everlasto
  // *     example 1: array_diff_key({red: 1, green: 2, blue: 3, white: 4}, {red: 5});
  // *     returns 1: {"green":2, "blue":3, "white":4}
  // *     example 2: array_diff_key({red: 1, green: 2, blue: 3, white: 4}, {red: 5}, {red: 5});
  // *     returns 2: {"green":2, "blue":3, "white":4}
  var argl = arguments.length,
    retArr = {},
    k1 = '',
    i = 1,
    k = '',
    arr = {};

  arr1keys: for (k1 in arr1) {
    for (i = 1; i < argl; i++) {
      arr = arguments[i];
      for (k in arr) {
        if (k === k1) {
          // If it reaches here, it was found in at least one array, so try next value
          continue arr1keys;
        }
      }
      retArr[k1] = arr1[k1];
    }
  }

  return retArr;
}
